1. Field of the Invention
The invention relates to a vehicle user interface unit, and more particularly, to a vehicle interface unit for a vehicle electronic device and a vehicle infotainment system, and methods for operating the vehicle interface unit.
2. Related Art
Vehicles are typically equipped with a user interface to allow the user (driver or passenger) to control functions relating to the vehicle itself or to an electronic device provided in the vehicle, such as an infotainment system. The user may be provided with control over functions and information or with a display of information that may relate to driver assistance systems, a multimedia system such as a car radio or mobile communication systems that communicate for example, via GSM or UMTS. Information from outside the vehicle may also be made available to the driver or passenger. For example, information may be received from communications systems that permit information retrieval and transmission from the car to the world, including for example, communication from car to car, or from car to infrastructure.
The user typically interacts with a head unit having a user interface with a display and control elements that allow the user to control the desired functions. The head unit typically has a face plate on the dashboard of the vehicle. Vehicles have limited space on the dashboard and the face plate, therefore, the mechanical control elements and the display may have to share the limited amount of space available in the dashboard with each other and with other components. The space limitation may limit the amount of information that may be simultaneously displayed to the user. In addition, only a few control elements may be available to operate and control a larger number of functions that may be offered to the user.
User access to the larger number of functions via a few control elements is generally achieved using a menu tree structure with main menus and multiple submenus, through which a user browses to reach a particular function. Menu structures may be cumbersome for the user. Browsing through the menus and submenus may take a considerable amount of time before the user reaches a particular menu item. During this time, if the user is also driving, the effort to find the desired menu item may distract the user sufficiently to create a dangerous situation.
One solution uses speech recognition for voice-activated commands to access the functions. However, such solutions have not yielded any considerable improvement due to the numerous enquiries by the system and the browsing through the menu structure still required by voice-activated commands.
Some improvement may be achieved using a touch screen, which replaces many of the mechanical control elements with graphical control elements. By removing the mechanical control elements, space becomes available on the face plate for a larger size display without needing a larger face plate. Nevertheless, the available physical space typically remains rather limited permitting a limited amount of information or menu items to be displayed resulting in a generally confusing presentation, particularly when accessing complex menu structures. The control elements are also graphically relatively small and fail to provide any haptic feedback. User interfaces having a touchscreen are not considerably easier to operate inside a vehicle, particularly when attempted by the driver. Touchscreens are also susceptible to becoming soiled, such as by fingerprints, deteriorating the quality of the displayed image.
There is a need for an improved presentation of menu structures and other information, and for facilitating the selection of menu items for controlling the functions of a vehicle electronic device, the vehicle itself or for adjusting parameters.